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排序方式: 共有1198条查询结果,搜索用时 15 毫秒
51.
Eric Parent Marie Archambault Audrey Charlebois Jocelyn Bernier-Lachance 《Avian pathology》2017,46(2):138-149
Necrotic enteritis (NE) is a major problem in antibiotic-free (ABF) chicken flocks and specific strains of Clostridium perfringens are known to induce NE. The objective of this study was to develop a chicken intestinal ligated loop model in order to compare the virulence of various C. perfringens strains recovered from consecutive ABF flocks with and without NE. Intestinal loops were surgically prepared in 10 anaesthetized specific-pathogen-free chickens and alternately inoculated with C. perfringens isolates or brain heart infusion (BHI) media. Histological lesion scoring was performed for each loop. All strains from NE-affected flocks induced histological lesions compatible with NE whereas inoculation of loops with a commensal C. perfringens strain or BHI did not. Among inoculated strains, CP0994 (netB-positive and cpb2-positive) and CP-2003-1256 (netB-positive) demonstrated mean histological lesion scores significantly higher (P?0.01) than those obtained with a commensal strain or BHI whereas strain CP1073 (netB-negative and cpb2-positive) induced intestinal lesions without significantly higher scores. In loops where villi were colonized by Gram-positive rods, significantly higher (P?0.01) mean histological lesion scores were observed. This result supports the hypothesis that colonization of the intestinal mucosa by C. perfringens is a critical step in the pathogenesis of NE. Finally, we demonstrated the importance of controlling virulent C. perfringens strains in ABF chicken flocks as a highly virulent strain can be present in consecutive flocks with NE and possibly affect multiple flocks. 相似文献
52.
Striatonigral axons co-release GABA and substance P (SP) at their target sites, but little is known about the action of SP at nigral level. Therefore, we studied immunohistochemically the cellular and subcellular localization of SP and its high affinity receptors neurokinin-1 (NK-1R) and neurokinin-3 (NK-3R) at nigral level in squirrel monkeys. Immunofluorescent studies revealed that, although SP+ fibers arborised more densely in the pars reticulata (SNr) than in the pars compacta (SNc), the two nigral divisions harbored numerous neurons expressing NK-1R and NK-3R. Confocal microscopic analyses showed that numerous SNr neurons and virtually all SNc dopaminergic neurons contained both NK-1R and NK-3R. At the electron microscope level, NK-1R and NK-3R were mainly associated with intracellular sites or located at extrasynaptic position on plasma membrane. A small proportion of SP+ boutons also showed NK-3R immunoreactivity. The distribution of NK-1R and NK-3R in SNr and SNc suggests that SP exerts its effect through postsynaptic receptors, as well as via presynaptic autoreceptors and heteroreceptors. These findings indicate that the excitatory peptide SP can modulate the inhibitory action of GABA at nigral level and suggest that the co-release of these two neuroactive substances should be taken into account when considering the functional organization of the basal ganglia. 相似文献
53.
Deborah J. Jones Rex Forehand Jessica Cuellar Carlye Kincaid Justin Parent Nicole Fenton Nada Goodrum 《Clinical psychology review》2013,33(2):241-252
Disruptive behaviors of childhood are among the most common reasons for referral of children to mental health professionals. Behavioral parent training (BPT) is the most efficacious intervention for these problem behaviors, yet BPT is substantially underutilized beyond university research and clinic settings. With the aim of addressing this research-to-practice gap, this article highlights the considerable, but largely unrealized, potential for technology to overcome the two most pressing challenges hindering the diffusion of BPT: (1). The dearth of BPT training and supervision opportunities for therapists who work with families of children with disruptive behaviors; and (2). The failure to engage and retain families in BPT services when services are available. To this end, this review presents a theoretical framework to guide technological innovations in BPT and highlights examples of how technology is currently being harnessed to overcome these challenges. This review also discusses recommendations for using technology as a delivery vehicle to further advance the field of BPT and the potential implications of technological innovations in BPT for other areas of children's mental health are discussed. 相似文献
54.
Matthew VanLandingham Tuan V. Nguyen Omar A. Abdul-Rahman Andrew Parent Jun Zhang 《Neurological sciences》2008,29(6):467-470
In this case report, we describe two siblings with a previously unreported partial monosomy 4q and partial trisomy 9q. The
sibling karyotypes were determined to be 46,XX,der(4)t(4;9)(q33;q33)pat and 46,XY,der(4)t(4;9)-(q33;q33)pat. The siblings
share several common pathological features, including VSD, PDA, low-set ears and digit anomalies as well as features consistent
with Pierre-Robin syndrome and hydrocephalus. We review previously reported phenotypes associated with monosomy 4q and partial
trisomy 9q and discuss potential mechanisms for these morphological insults with particular emphasis on neuropathology. 相似文献
55.
56.
Étienne Bourassa-Moreau Jean-Marc Mac-Thiong Julie Joncas Stefan Parent Hubert Labelle 《The spine journal》2013,13(7):770-774
Background contextSurgical intervention is generally indicated in a pediatric high-grade spondylolisthesis to prevent the progression of deformity or neurologic deterioration and improve the quality of life. However, the outcome of the treatment on the health-related quality of life (HRQOL) of patients with high-grade spondylolisthesis remains largely unknown.PurposeTo describe the changes in the HRQOL of patients with pediatric high-grade spondylolisthesis after surgical and nonsurgical managements.Study designObservational case series with a minimal of 2-year follow-up.Patient sampleTwenty-eight pediatric patients with high-grade spondylolisthesis from a single institution filled the inclusion criteria. Twenty-three patients were managed surgically and five were managed nonsurgically.Outcome measuresSelf-report measures: Scoliosis Research Society questionnaires (SRS-22). Neurologic examination, radiographic evaluation of slip grade.MethodsThe SRS-22 questionnaire was collected at the baseline (initial presentation for the nonsurgical group and preoperative visit for the surgical group) and at the last follow-up. Differences between baseline and last follow-up were evaluated in both groups. Correlation between the baseline score of SRS-22 score and improvement in the SRS-22 score was determined in surgical patients.ResultsIn surgical patients, total SRS-22 scores were 3.31±0.50 at the baseline and 4.26±0.50 at the last follow-up. In nonsurgical patients, total SRS-22 scores were 4.12±0.16 at the baseline and 4.14±0.38 at the last follow-up. Therefore, variation in the SRS-22 total score was +0.94±0.77 (p<.001) for surgical patients and +0.02 ± 0.35 (p=.854) for nonsurgical patients. Improvement of the SRS-22 score was correlated with a low baseline value of SRS-22 (R²=0.61; p<.001). There was no neurologic or slip deterioration during the follow-up for patients treated nonsurgically.ConclusionsThe HRQOL improves after a surgical intervention for high-grade spondylolisthesis. Patients with lower baseline HRQOL scores are those who benefit the most from surgery. Close observation is a safe and feasible option in selected patients with a good baseline HRQOL and no neurologic impairment. 相似文献
57.
58.
OBJECTIVES: The purpose of this study was to determine whether vicarious experience, in which former patients exemplify the active lives they are leading, reduces anxiety and increases self-efficacy expectation and self-reported activity in patients after cardiac surgery. DESIGN: A randomized, controlled trial was used to evaluate an intervention that linked volunteers who had recovered from cardiac surgery in dyadic support with patients about to undergo similar surgery. The linking was achieved by means of visits during the hospitalization and recovery period. SUBJECTS: Fifty-six first-time male patients undergoing coronary artery bypass graft (CABG) surgery, with a mean age of 56.5 years, were randomly assigned to an experimental (n = 27) or control group (n = 29). Outcome Measures: Anxiety was measured at 48 hours and 24 hours before surgery, and again at 5 days and 4 weeks after surgery. Self-efficacy expectation and self-reported activity were both evaluated at 5 days and 4 weeks after surgery. RESULTS: Only the experimental group showed a significant decrease in anxiety during hospitalization. At all measurement times after the first intervention, the experimental group reported significantly lower levels of anxiety compared with the control group. The experimental group reported significantly higher levels of self-efficacy expectation and self-reported activity for general activities, walking, and climbing stairs evaluated at 5 days, and for general activities at 4 weeks after surgery. CONCLUSIONS: Vicarious experience provided through dyadic support is effective in helping patients undergoing cardiac surgery cope with surgical anxiety and in improving self-efficacy expectations and self-reported activity after surgery. Dyadic support is a valuable tool for recovery from cardiac surgery that needs to be maintained and explored through nursing practice and research. 相似文献
59.
J. Gaudin C. Le Treguilly P. Parent H. Le Guern J. J. Chabaud G. Boog B. Jehannin 《Pediatric surgery international》1988,3(2-3):158-164
Twelve cases of ovarian cysts are reported. The diagnosis was made antenatally by ultrasound scan. The authors consider the ultrasonic images of these cysts and signs of in-utero torsion, the antenatal and postnatal evolution, the pathological findings at surgery, and the histological results for six children that were operated. A review of the literature enables us to describe the possible complications in the evolution of this tumor and to discuss the perinatal management of the ovarian cyst, which depends on the appearance and diameter of the cyst and on its evolution.
Offprint requests to: J. Gaudin 相似文献
60.